diff options
| -rw-r--r-- | Documentation/DocBook/gadget.tmpl | 35 | ||||
| -rw-r--r-- | drivers/usb/gadget/composite.c | 1040 | ||||
| -rw-r--r-- | include/linux/usb/composite.h | 338 |
3 files changed, 1413 insertions, 0 deletions
diff --git a/Documentation/DocBook/gadget.tmpl b/Documentation/DocBook/gadget.tmpl index 5a8ffa761e0..478bfe16a19 100644 --- a/Documentation/DocBook/gadget.tmpl +++ b/Documentation/DocBook/gadget.tmpl @@ -524,6 +524,41 @@ These utilities include endpoint autoconfiguration. <!-- !Edrivers/usb/gadget/epautoconf.c --> </sect1> +<sect1 id="composite"><title>Composite Device Framework</title> + +<para>The core API is sufficient for writing drivers for composite +USB devices (with more than one function in a given configuration), +and also multi-configuration devices (also more than one function, +but not necessarily sharing a given configuration). +There is however an optional framework which makes it easier to +reuse and combine functions. +</para> + +<para>Devices using this framework provide a <emphasis>struct +usb_composite_driver</emphasis>, which in turn provides one or +more <emphasis>struct usb_configuration</emphasis> instances. +Each such configuration includes at least one +<emphasis>struct usb_function</emphasis>, which packages a user +visible role such as "network link" or "mass storage device". +Management functions may also exist, such as "Device Firmware +Upgrade". +</para> + +!Iinclude/linux/usb/composite.h +!Edrivers/usb/gadget/composite.c + +</sect1> + +<sect1 id="functions"><title>Composite Device Functions</title> + +<para>At this writing, a few of the current gadget drivers have +been converted to this framework. +Near-term plans include converting all of them, except for "gadgetfs". +</para> + +</sect1> + + </chapter> <chapter id="controllers"><title>Peripheral Controller Drivers</title> diff --git a/drivers/usb/gadget/composite.c b/drivers/usb/gadget/composite.c new file mode 100644 index 00000000000..b3d302a6a08 --- /dev/null +++ b/drivers/usb/gadget/composite.c @@ -0,0 +1,1040 @@ +/* + * composite.c - infrastructure for Composite USB Gadgets + * + * Copyright (C) 2006-2008 David Brownell + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +/* #define VERBOSE_DEBUG */ + +#include <linux/kallsyms.h> +#include <linux/kernel.h> +#include <linux/slab.h> +#include <linux/device.h> + +#include <linux/usb/composite.h> + + +/* + * The code in this file is utility code, used to build a gadget driver + * from one or more "function" drivers, one or more "configuration" + * objects, and a "usb_composite_driver" by gluing them together along + * with the relevant device-wide data. + */ + +/* big enough to hold our biggest descriptor */ +#define USB_BUFSIZ 512 + +static struct usb_composite_driver *composite; + +/* Some systems will need runtime overrides for the product identifers + * published in the device descriptor, either numbers or strings or both. + * String parameters are in UTF-8 (superset of ASCII's 7 bit characters). + */ + +static ushort idVendor; +module_param(idVendor, ushort, 0); +MODULE_PARM_DESC(idVendor, "USB Vendor ID"); + +static ushort idProduct; +module_param(idProduct, ushort, 0); +MODULE_PARM_DESC(idProduct, "USB Product ID"); + +static ushort bcdDevice; +module_param(bcdDevice, ushort, 0); +MODULE_PARM_DESC(bcdDevice, "USB Device version (BCD)"); + +static char *iManufacturer; +module_param(iManufacturer, charp, 0); +MODULE_PARM_DESC(iManufacturer, "USB Manufacturer string"); + +static char *iProduct; +module_param(iProduct, charp, 0); +MODULE_PARM_DESC(iProduct, "USB Product string"); + +static char *iSerialNumber; +module_param(iSerialNumber, charp, 0); +MODULE_PARM_DESC(iSerialNumber, "SerialNumber string"); + +/*-------------------------------------------------------------------------*/ + +/** + * usb_add_function() - add a function to a configuration + * @config: the configuration + * @function: the function being added + * Context: single threaded during gadget setup + * + * After initialization, each configuration must have one or more + * functions added to it. Adding a function involves calling its @bind() + * method to allocate resources such as interface and string identifiers + * and endpoints. + * + * This function returns the value of the function's bind(), which is + * zero for success else a negative errno value. + */ +int __init usb_add_function(struct usb_configuration *config, + struct usb_function *function) +{ + int value = -EINVAL; + + DBG(config->cdev, "adding '%s'/%p to config '%s'/%p\n", + function->name, function, + config->label, config); + + if (!function->set_alt || !function->disable) + goto done; + + function->config = config; + list_add_tail(&function->list, &config->functions); + + /* REVISIT *require* function->bind? */ + if (function->bind) { + value = function->bind(config, function); + if (value < 0) { + list_del(&function->list); + function->config = NULL; + } + } else + value = 0; + + /* We allow configurations that don't work at both speeds. + * If we run into a lowspeed Linux system, treat it the same + * as full speed ... it's the function drivers that will need + * to avoid bulk and ISO transfers. + */ + if (!config->fullspeed && function->descriptors) + config->fullspeed = true; + if (!config->highspeed && function->hs_descriptors) + config->highspeed = true; + +done: + if (value) + DBG(config->cdev, "adding '%s'/%p --> %d\n", + function->name, function, value); + return value; +} + +/** + * usb_interface_id() - allocate an unused interface ID + * @config: configuration associated with the interface + * @function: function handling the interface + * Context: single threaded during gadget setup + * + * usb_interface_id() is called from usb_function.bind() callbacks to + * allocate new interface IDs. The function driver will then store that + * ID in interface, association, CDC union, and other descriptors. It + * will also handle any control requests targetted at that interface, + * particularly changing its altsetting via set_alt(). There may + * also be class-specific or vendor-specific requests to handle. + * + * All interface identifier should be allocated using this routine, to + * ensure that for example different functions don't wrongly assign + * different meanings to the same identifier. Note that since interface + * identifers are configuration-specific, functions used in more than + * one configuration (or more than once in a given configuration) need + * multiple versions of the relevant descriptors. + * + * Returns the interface ID which was allocated; or -ENODEV if no + * more interface IDs can be allocated. + */ +int __init usb_interface_id(struct usb_configuration *config, + struct usb_function *function) +{ + unsigned id = config->next_interface_id; + + if (id < MAX_CONFIG_INTERFACES) { + config->interface[id] = function; + config->next_interface_id = id + 1; + return id; + } + return -ENODEV; +} + +static int config_buf(struct usb_configuration *config, + enum usb_device_speed speed, void *buf, u8 type) +{ + struct usb_config_descriptor *c = buf; + void *next = buf + USB_DT_CONFIG_SIZE; + int len = USB_BUFSIZ - USB_DT_CONFIG_SIZE; + struct usb_function *f; + int status; + + /* write the config descriptor */ + c = buf; + c->bLength = USB_DT_CONFIG_SIZE; + c->bDescriptorType = type; + /* wTotalLength is written later */ + c->bNumInterfaces = config->next_interface_id; + c->bConfigurationValue = config->bConfigurationValue; + c->iConfiguration = config->iConfiguration; + c->bmAttributes = USB_CONFIG_ATT_ONE | config->bmAttributes; + c->bMaxPower = config->bMaxPower; + + /* There may be e.g. OTG descriptors */ + if (config->descriptors) { + status = usb_descriptor_fillbuf(next, len, + config->descriptors); + if (status < 0) + return status; + len -= status; + next += status; + } + + /* add each function's descriptors */ + list_for_each_entry(f, &config->functions, list) { + struct usb_descriptor_header **descriptors; + + if (speed == USB_SPEED_HIGH) + descriptors = f->hs_descriptors; + else + descriptors = f->descriptors; + if (!descriptors) + continue; + status = usb_descriptor_fillbuf(next, len, + (const struct usb_descriptor_header **) descriptors); + if (status < 0) + return status; + len -= status; + next += status; + } + + len = next - buf; + c->wTotalLength = cpu_to_le16(len); + return len; +} + +static int config_desc(struct usb_composite_dev *cdev, unsigned w_value) +{ + struct usb_gadget *gadget = cdev->gadget; + struct usb_configuration *c; + u8 type = w_value >> 8; + enum usb_device_speed speed = USB_SPEED_UNKNOWN; + + if (gadget_is_dualspeed(gadget)) { + int hs = 0; + + if (gadget->speed == USB_SPEED_HIGH) + hs = 1; + if (type == USB_DT_OTHER_SPEED_CONFIG) + hs = !hs; + if (hs) + speed = USB_SPEED_HIGH; + + } + + /* This is a lookup by config *INDEX* */ + w_value &= 0xff; + list_for_each_entry(c, &cdev->configs, list) { + /* ignore configs that won't work at this speed */ + if (speed == USB_SPEED_HIGH) { + if (!c->highspeed) + continue; + } else { + if (!c->fullspeed) + continue; + } + if (w_value == 0) + return config_buf(c, speed, cdev->req->buf, type); + w_value--; + } + return -EINVAL; +} + +static int count_configs(struct usb_composite_dev *cdev, unsigned type) +{ + struct usb_gadget *gadget = cdev->gadget; + struct usb_configuration *c; + unsigned count = 0; + int hs = 0; + + if (gadget_is_dualspeed(gadget)) { + if (gadget->speed == USB_SPEED_HIGH) + hs = 1; + if (type == USB_DT_DEVICE_QUALIFIER) + hs = !hs; + } + list_for_each_entry(c, &cdev->configs, list) { + /* ignore configs that won't work at this speed */ + if (hs) { + if (!c->highspeed) + continue; + } else { + if (!c->fullspeed) + continue; + } + count++; + } + return count; +} + +static void device_qual(struct usb_composite_dev *cdev) +{ + struct usb_qualifier_descriptor *qual = cdev->req->buf; + + qual->bLength = sizeof(*qual); + qual->bDescriptorType = USB_DT_DEVICE_QUALIFIER; + /* POLICY: same bcdUSB and device type info at both speeds */ + qual->bcdUSB = cdev->desc.bcdUSB; + qual->bDeviceClass = cdev->desc.bDeviceClass; + qual->bDeviceSubClass = cdev->desc.bDeviceSubClass; + qual->bDeviceProtocol = cdev->desc.bDeviceProtocol; + /* ASSUME same EP0 fifo size at both speeds */ + qual->bMaxPacketSize0 = cdev->desc.bMaxPacketSize0; + qual->bNumConfigurations = count_configs(cdev, USB_DT_DEVICE_QUALIFIER); +} + +/*-------------------------------------------------------------------------*/ + +static void reset_config(struct usb_composite_dev *cdev) +{ + struct usb_function *f; + + DBG(cdev, "reset config\n"); + + list_for_each_entry(f, &cdev->config->functions, list) { + if (f->disable) + f->disable(f); + } + cdev->config = NULL; +} + +static int set_config(struct usb_composite_dev *cdev, + const struct usb_ctrlrequest *ctrl, unsigned number) +{ + struct usb_gadget *gadget = cdev->gadget; + struct usb_configuration *c = NULL; + int result = -EINVAL; + unsigned power = gadget_is_otg(gadget) ? 8 : 100; + int tmp; + + if (cdev->config) + reset_config(cdev); + + if (number) { + list_for_each_entry(c, &cdev->configs, list) { + if (c->bConfigurationValue == number) { + result = 0; + break; + } + } + if (result < 0) + goto done; + } else + result = 0; + + INFO(cdev, "%s speed config #%d: %s\n", + ({ char *speed; + switch (gadget->speed) { + case USB_SPEED_LOW: speed = "low"; break; + case USB_SPEED_FULL: speed = "full"; break; + case USB_SPEED_HIGH: speed = "high"; break; + default: speed = "?"; break; + } ; speed; }), number, c ? c->label : "unconfigured"); + + if (!c) + goto done; + + cdev->config = c; + + /* Initialize all interfaces by setting them to altsetting zero. */ + for (tmp = 0; tmp < MAX_CONFIG_INTERFACES; tmp++) { + struct usb_function *f = c->interface[tmp]; + + if (!f) + break; + + result = f->set_alt(f, tmp, 0); + if (result < 0) { + DBG(cdev, "interface %d (%s/%p) alt 0 --> %d\n", + tmp, f->name, f, result); + + reset_config(cdev); + goto done; + } + } + + /* when we return, be sure our power usage is valid */ + power = 2 * c->bMaxPower; +done: + usb_gadget_vbus_draw(gadget, power); + return result; +} + +/** + * usb_add_config() - add a configuration to a device. + * @cdev: wraps the USB gadget + * @config: the configuration, with bConfigurationValue assigned + * Context: single threaded during gadget setup + * + * One of the main tasks of a composite driver's bind() routine is to + * add each of the configurations it supports, using this routine. + * + * This function returns the value of the configuration's bind(), which + * is zero for success else a negative errno value. Binding configurations + * assigns global resources including string IDs, and per-configuration + * resources such as interface IDs and endpoints. + */ +int __init usb_add_config(struct usb_composite_dev *cdev, + struct usb_configuration *config) +{ + int status = -EINVAL; + struct usb_configuration *c; + + DBG(cdev, "adding config #%u '%s'/%p\n", + config->bConfigurationValue, + config->label, config); + + if (!config->bConfigurationValue || !config->bind) + goto done; + + /* Prevent duplicate configuration identifiers */ + list_for_each_entry(c, &cdev->configs, list) { + if (c->bConfigurationValue == config->bConfigurationValue) { + status = -EBUSY; + goto done; + } + } + + config->cdev = cdev; + list_add_tail(&config->list, &cdev->configs); + + INIT_LIST_HEAD(&config->functions); + config->next_interface_id = 0; + + status = config->bind(config); + if (status < 0) { + list_del(&config->list); + config->cdev = NULL; + } else { + unsigned i; + + DBG(cdev, "cfg %d/%p speeds:%s%s\n", + config->bConfigurationValue, config, + config->highspeed ? " high" : "", + config->fullspeed + ? (gadget_is_dualspeed(cdev->gadget) + ? " full" + : " full/low") + : ""); + + for (i = 0; i < MAX_CONFIG_INTERFACES; i++) { + struct usb_function *f = config->interface[i]; + + if (!f) + continue; + DBG(cdev, " interface %d = %s/%p\n", + i, f->name, f); + } + } + + /* set_alt(), or next config->bind(), sets up + * ep->driver_data as needed. + */ + usb_ep_autoconfig_reset(cdev->gadget); + +done: + if (status) + DBG(cdev, "added config '%s'/%u --> %d\n", config->label, + config->bConfigurationValue, status); + return status; +} + +/*-------------------------------------------------------------------------*/ + +/* We support strings in multiple languages ... string descriptor zero + * says which languages are supported. The typical case will be that + * only one language (probably English) is used, with I18N handled on + * the host side. + */ + +static void collect_langs(struct usb_gadget_strings **sp, __le16 *buf) +{ + const struct usb_gadget_strings *s; + u16 language; + __le16 *tmp; + + while (*sp) { + s = *sp; + language = cpu_to_le16(s->language); + for (tmp = buf; *tmp && tmp < &buf[126]; tmp++) { + if (*tmp == language) + goto repeat; + } + *tmp++ = language; +repeat: + sp++; + } +} + +static int lookup_string( + struct usb_gadget_strings **sp, + void *buf, + u16 language, + int id +) +{ + struct usb_gadget_strings *s; + int value; + + while (*sp) { + s = *sp++; + if (s->language != language) + continue; + value = usb_gadget_get_string(s, id, buf); + if (value > 0) + return value; + } + return -EINVAL; +} + +static int get_string(struct usb_composite_dev *cdev, + void *buf, u16 language, int id) +{ + struct usb_configuration *c; + struct usb_function *f; + int len; + + /* Yes, not only is USB's I18N support probably more than most + * folk will ever care about ... also, it's all supported here. + * (Except for UTF8 support for Unicode's "Astral Planes".) + */ + + /* 0 == report all available language codes */ + if (id == 0) { + struct usb_string_descriptor *s = buf; + struct usb_gadget_strings **sp; + + memset(s, 0, 256); + s->bDescriptorType = USB_DT_STRING; + + sp = composite->strings; + if (sp) + collect_langs(sp, s->wData); + + list_for_each_entry(c, &cdev->configs, list) { + sp = c->strings; + if (sp) + collect_langs(sp, s->wData); + + list_for_each_entry(f, &c->functions, list) { + sp = f->strings; + if (sp) + collect_langs(sp, s->wData); + } + } + + for (len = 0; s->wData[len] && len <= 126; len++) + continue; + if (!len) + return -EINVAL; + + s->bLength = 2 * (len + 1); + return s->bLength; + } + + /* Otherwise, look up and return a specified string. String IDs + * are device-scoped, so we look up each string table we're told + * about. These lookups are infrequent; simpler-is-better here. + */ + if (composite->strings) { + len = lookup_string(composite->strings, buf, language, id); + if (len > 0) + return len; + } + list_for_each_entry(c, &cdev->configs, list) { + if (c->strings) { + len = lookup_string(c->strings, buf, language, id); + if (len > 0) + return len; + } + list_for_each_entry(f, &c->functions, list) { + if (!f->strings) + continue; + len = lookup_string(f->strings, buf, language, id); + if (len > 0) + return len; + } + } + return -EINVAL; +} + +/** + * usb_string_id() - allocate an unused string ID + * @cdev: the device whose string descriptor IDs are being allocated + * Context: single threaded during gadget setup + * + * @usb_string_id() is called from bind() callbacks to allocate + * string IDs. Drivers for functions, configurations, or gadgets will + * then store that ID in the appropriate descriptors and string table. + * + * All string identifier should be allocated using this routine, to + * ensure that for example different functions don't wrongly assign + * different meanings to the same identifier. + */ +int __init usb_string_id(struct usb_composite_dev *cdev) +{ + if (cdev->next_string_id < 254) { + /* string id 0 is reserved */ + cdev->next_string_id++; + return cdev->next_string_id; + } + return -ENODEV; +} + +/*-------------------------------------------------------------------------*/ + +static void composite_setup_complete(struct usb_ep *ep, struct usb_request *req) +{ + if (req->status || req->actual != req->length) + DBG((struct usb_composite_dev *) ep->driver_data, + "setup complete --> %d, %d/%d\n", + req->status, req->actual, req->length); +} + +/* + * The setup() callback implements all the ep0 functionality that's + * not handled lower down, in hardware or the hardware driver(like + * device and endpoint feature flags, and their status). It's all + * housekeeping for the gadget function we're implementing. Most of + * the work is in config and function specific setup. + */ +static int +composite_setup(struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl) +{ + struct usb_composite_dev *cdev = get_gadget_data(gadget); + struct usb_request *req = cdev->req; + int value = -EOPNOTSUPP; + u16 w_index = le16_to_cpu(ctrl->wIndex); + u16 w_value = le16_to_cpu(ctrl->wValue); + u16 w_length = le16_to_cpu(ctrl->wLength); + struct usb_function *f = NULL; + + /* partial re-init of the response message; the function or the + * gadget might need to intercept e.g. a control-OUT completion + * when we delegate to it. + */ + req->zero = 0; + req->complete = composite_setup_complete; + req->length = USB_BUFSIZ; + gadget->ep0->driver_data = cdev; + + switch (ctrl->bRequest) { + + /* we handle all standard USB descriptors */ + case USB_REQ_GET_DESCRIPTOR: + if (ctrl->bRequestType != USB_DIR_IN) + goto unknown; + switch (w_value >> 8) { + + case USB_DT_DEVICE: + cdev->desc.bNumConfigurations = + count_configs(cdev, USB_DT_DEVICE); + value = min(w_length, (u16) sizeof cdev->desc); + memcpy(req->buf, &cdev->desc, value); + break; + case USB_DT_DEVICE_QUALIFIER: + if (!gadget_is_dualspeed(gadget)) + break; + device_qual(cdev); + value = min_t(int, w_length, + sizeof(struct usb_qualifier_descriptor)); + break; + case USB_DT_OTHER_SPEED_CONFIG: + if (!gadget_is_dualspeed(gadget)) + break; + /* FALLTHROUGH */ + case USB_DT_CONFIG: + value = config_desc(cdev, w_value); + if (value >= 0) + value = min(w_length, (u16) value); + break; + case USB_DT_STRING: + value = get_string(cdev, req->buf, + w_index, w_value & 0xff); + if (value >= 0) + value = min(w_length, (u16) value); + break; + } + break; + + /* any number of configs can work */ + case USB_REQ_SET_CONFIGURATION: + if (ctrl->bRequestType != 0) + goto unknown; + if (gadget_is_otg(gadget)) { + if (gadget->a_hnp_support) + DBG(cdev, "HNP available\n"); + else if (gadget->a_alt_hnp_support) + DBG(cdev, "HNP on another port\n"); + else + VDBG(cdev, "HNP inactive\n"); + } + spin_lock(&cdev->lock); + value = set_config(cdev, ctrl, w_value); + spin_unlock(&cdev->lock); + break; + case USB_REQ_GET_CONFIGURATION: + if (ctrl->bRequestType != USB_DIR_IN) + goto unknown; + if (cdev->config) + *(u8 *)req->buf = cdev->config->bConfigurationValue; + else + *(u8 *)req->buf = 0; + value = min(w_length, (u16) 1); + break; + + /* function drivers must handle get/set altsetting; if there's + * no get() method, we know only altsetting zero works. + */ + case USB_REQ_SET_INTERFACE: + if (ctrl->bRequestType != USB_RECIP_INTERFACE) + goto unknown; + if (!cdev->config || w_index >= MAX_CONFIG_INTERFACES) + break; + f = cdev->config->interface[w_index]; + if (!f) + break; + if (w_value && !f->get_alt) + break; + value = f->set_alt(f, w_index, w_value); + break; + case USB_REQ_GET_INTERFACE: + if (ctrl->bRequestType != (USB_DIR_IN|USB_RECIP_INTERFACE)) + goto unknown; + if (!cdev->config || w_index >= MAX_CONFIG_INTERFACES) + break; + f = cdev->config->interface[w_index]; + if (!f) + break; + /* lots of interfaces only need altsetting zero... */ + value = f->get_alt ? f->get_alt(f, w_index) : 0; + if (value < 0) + break; + *((u8 *)req->buf) = value; + value = min(w_length, (u16) 1); + break; + default: +unknown: + VDBG(cdev, + "non-core control req%02x.%02x v%04x i%04x l%d\n", + ctrl->bRequestType, ctrl->bRequest, + w_value, w_index, w_length); + + /* functions always handle their interfaces ... punt other + * recipients (endpoint, other, WUSB, ...) to the current + * configuration code. + * + * REVISIT it could make sense to let the composite device + * take such requests too, if that's ever needed: to work + * in config 0, etc. + */ + if ((ctrl->bRequestType & USB_RECIP_MASK) + == USB_RECIP_INTERFACE) { + f = cdev->config->interface[w_index]; + if (f && f->setup) + value = f->setup(f, ctrl); + else + f = NULL; + } + if (value < 0 && !f) { + struct usb_configuration *c; + + c = cdev->config; + if (c && c->setup) + value = c->setup(c, ctrl); + } + + goto done; + } + + /* respond with data transfer before status phase? */ + if (value >= 0) { + req->length = value; + req->zero = value < w_length; + value = usb_ep_queue(gadget->ep0, req, GFP_ATOMIC); + if (value < 0) { + DBG(cdev, "ep_queue --> %d\n", value); + req->status = 0; + composite_setup_complete(gadget->ep0, req); + } + } + +done: + /* device either stalls (value < 0) or reports success */ + return value; +} + +static void composite_disconnect(struct usb_gadget *gadget) +{ + struct usb_composite_dev *cdev = get_gadget_data(gadget); + unsigned long flags; + + /* REVISIT: should we have config and device level + * disconnect callbacks? + */ + spin_lock_irqsave(&cdev->lock, flags); + if (cdev->config) + reset_config(cdev); + spin_unlock_irqrestore(&cdev->lock, flags); +} + +/*-------------------------------------------------------------------------*/ + +static void /* __init_or_exit */ +composite_unbind(struct usb_gadget *gadget) +{ + struct usb_composite_dev *cdev = get_gadget_data(gadget); + + /* composite_disconnect() must already have been called + * by the underlying peripheral controller driver! + * so there's no i/o concurrency that could affect the + * state protected by cdev->lock. + */ + WARN_ON(cdev->config); + + while (!list_empty(&cdev->configs)) { + struct usb_configuration *c; + + c = list_first_entry(&cdev->configs, + struct usb_configuration, list); + while (!list_empty(&c->functions)) { + struct usb_function *f; + + f = list_first_entry(&c->functions, + struct usb_function, list); + list_del(&f->list); + if (f->unbind) { + DBG(cdev, "unbind function '%s'/%p\n", + f->name, f); + f->unbind(c, f); + /* may free memory for "f" */ + } + } + list_del(&c->list); + if (c->unbind) { + DBG(cdev, "unbind config '%s'/%p\n", c->label, c); + c->unbind(c); + /* may free memory for "c" */ + } + } + if (composite->unbind) + composite->unbind(cdev); + + if (cdev->req) { + kfree(cdev->req->buf); + usb_ep_free_request(gadget->ep0, cdev->req); + } + kfree(cdev); + set_gadget_data(gadget, NULL); + composite = NULL; +} + +static void __init +string_override_one(struct usb_gadget_strings *tab, u8 id, const char *s) +{ + struct usb_string *str = tab->strings; + + for (str = tab->strings; str->s; str++) { + if (str->id == id) { + str->s = s; + return; + } + } +} + +static void __init +string_override(struct usb_gadget_strings **tab, u8 id, const char *s) +{ + while (*tab) { + string_override_one(*tab, id, s); + tab++; + } +} + +static int __init composite_bind(struct usb_gadget *gadget) +{ + struct usb_composite_dev *cdev; + int status = -ENOMEM; + + cdev = kzalloc(sizeof *cdev, GFP_KERNEL); + if (!cdev) + return status; + + spin_lock_init(&cdev->lock); + cdev->gadget = gadget; + set_gadget_data(gadget, cdev); + INIT_LIST_HEAD(&cdev->configs); + + /* preallocate control response and buffer */ + cdev->req = usb_ep_alloc_request(gadget->ep0, GFP_KERNEL); + if (!cdev->req) + goto fail; + cdev->req->buf = kmalloc(USB_BUFSIZ, GFP_KERNEL); + if (!cdev->req->buf) + goto fail; + cdev->req->complete = composite_setup_complete; + gadget->ep0->driver_data = cdev; + + cdev->bufsiz = USB_BUFSIZ; + cdev->driver = composite; + + usb_gadget_set_selfpowered(gadget); + + /* interface and string IDs start at zero via kzalloc. + * we force endpoints to start unassigned; few controller + * drivers will zero ep->driver_data. + */ + usb_ep_autoconfig_reset(cdev->gadget); + + /* composite gadget needs to assign strings for whole device (like + * serial number), register function drivers, potentially update + * power state and consumption, etc + */ + status = composite->bind(cdev); + if (status < 0) + goto fail; + + cdev->desc = *composite->dev; + cdev->desc.bMaxPacketSize0 = gadget->ep0->maxpacket; + + /* standardized runtime overrides for device ID data */ + if (idVendor) + cdev->desc.idVendor = cpu_to_le16(idVendor); + if (idProduct) + cdev->desc.idProduct = cpu_to_le16(idProduct); + if (bcdDevice) + cdev->desc.bcdDevice = cpu_to_le16(bcdDevice); + + /* strings can't be assigned before bind() allocates the + * releavnt identifiers + */ + if (cdev->desc.iManufacturer && iManufacturer) + string_override(composite->strings, + cdev->desc.iManufacturer, iManufacturer); + if (cdev->desc.iProduct && iProduct) + string_override(composite->strings, + cdev->desc.iProduct, iProduct); + if (cdev->desc.iSerialNumber && iSerialNumber) + string_override(composite->strings, + cdev->desc.iSerialNumber, iSerialNumber); + + INFO(cdev, "%s ready\n", composite->name); + return 0; + +fail: + composite_unbind(gadget); + return status; +} + +/*-------------------------------------------------------------------------*/ + +static void +composite_suspend(struct usb_gadget *gadget) +{ + struct usb_composite_dev *cdev = get_gadget_data(gadget); + struct usb_function *f; + + /* REVISIT: should we have config and device level + * suspend/resume callbacks? + */ + DBG(cdev, "suspend\n"); + if (cdev->config) { + list_for_each_entry(f, &cdev->config->functions, list) { + if (f->suspend) + f->suspend(f); + } + } +} + +static void +composite_resume(struct usb_gadget *gadget) +{ + struct usb_composite_dev *cdev = get_gadget_data(gadget); + struct usb_function *f; + + /* REVISIT: should we have config and device level + * suspend/resume callbacks? + */ + DBG(cdev, "resume\n"); + if (cdev->config) { + list_for_each_entry(f, &cdev->config->functions, list) { + if (f->resume) + f->resume(f); + } + } +} + +/*-------------------------------------------------------------------------*/ + +static struct usb_gadget_driver composite_driver = { + .speed = USB_SPEED_HIGH, + + .bind = composite_bind, + .unbind = __exit_p(composite_unbind), + + .setup = composite_setup, + .disconnect = composite_disconnect, + + .suspend = composite_suspend, + .resume = composite_resume, + + .driver = { + .owner = THIS_MODULE, + }, +}; + +/** + * usb_composite_register() - register a composite driver + * @driver: the driver to register + * Context: single threaded during gadget setup + * + * This function is used to register drivers using the composite driver + * framework. The return value is zero, or a negative errno value. + * Those values normally come from the driver's @bind method, which does + * all the work of setting up the driver to match the hardware. + * + * On successful return, the gadget is ready to respond to requests from + * the host, unless one of its components invokes usb_gadget_disconnect() + * while it was binding. That would usually be done in order to wait for + * some userspace participation. + */ +int __init usb_composite_register(struct usb_composite_driver *driver) +{ + if (!driver || !driver->dev || !driver->bind || composite) + return -EINVAL; + + if (!driver->name) + driver->name = "composite"; + composite_driver.function = (char *) driver->name; + composite_driver.driver.name = driver->name; + composite = driver; + + return usb_gadget_register_driver(&composite_driver); +} + +/** + * usb_composite_unregister() - unregister a composite driver + * @driver: the driver to unregister + * + * This function is used to unregister drivers using the composite + * driver framework. + */ +void __exit usb_composite_unregister(struct usb_composite_driver *driver) +{ + if (composite != driver) + return; + usb_gadget_unregister_driver(&composite_driver); +} diff --git a/include/linux/usb/composite.h b/include/linux/usb/composite.h new file mode 100644 index 00000000000..747c3a49cdc --- /dev/null +++ b/include/linux/usb/composite.h @@ -0,0 +1,338 @@ +/* + * composite.h -- framework for usb gadgets which are composite devices + * + * Copyright (C) 2006-2008 David Brownell + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + */ + +#ifndef __LINUX_USB_COMPOSITE_H +#define __LINUX_USB_COMPOSITE_H + +/* + * This framework is an optional layer on top of the USB Gadget interface, + * making it easier to build (a) Composite devices, supporting multiple + * functions within any single configuration, and (b) Multi-configuration + * devices, also supporting multiple functions but without necessarily + * having more than one function per configuration. + * + * Example: a device with a single configuration supporting both network + * link and mass storage functions is a composite device. Those functions + * might alternatively be packaged in individual configurations, but in + * the composite model the host can use both functions at the same time. + */ + +#include <linux/usb/ch9.h> +#include <linux/usb/gadget.h> + + +struct usb_configuration; + +/** + * struct usb_function - describes one function of a configuration + * @name: For diagnostics, identifies the function. + * @strings: tables of strings, keyed by identifiers assigned during bind() + * and by language IDs provided in control requests + * @descriptors: Table of full (or low) speed descriptors, using interface and + * string identifiers assigned during @bind(). If this pointer is null, + * the function will not be available at full speed (or at low speed). + * @hs_descriptors: Table of high speed descriptors, using interface and + * string identifiers assigned during @bind(). If this pointer is null, + * the function will not be available at high speed. + * @config: assigned when @usb_add_function() is called; this is the + * configuration with which this function is associated. + * @bind: Before the gadget can register, all of its functions bind() to the + * available resources including string and interface identifiers used + * in interface or class descriptors; endpoints; I/O buffers; and so on. + * @unbind: Reverses @bind; called as a side effect of unregistering the + * driver which added this function. + * @set_alt: (REQUIRED) Reconfigures altsettings; function drivers may + * initialize usb_ep.driver data at this time (when it is used). + * Note that setting an interface to its current altsetting resets + * interface state, and that all interfaces have a disabled state. + * @get_alt: Returns the active altsetting. If this is not provided, + * then only altsetting zero is supported. + * @disable: (REQUIRED) Indicates the function should be disabled. Reasons + * include host resetting or reconfiguring the gadget, and disconnection. + * @setup: Used for interface-specific control requests. + * @suspend: Notifies functions when the host stops sending USB traffic. + * @resume: Notifies functions when the host restarts USB traffic. + * + * A single USB function uses one or more interfaces, and should in most + * cases support operation at both full and high speeds. Each function is + * associated by @usb_add_function() with a one configuration; that function + * causes @bind() to be called so resources can be allocated as part of + * setting up a gadget driver. Those resources include endpoints, which + * should be allocated using @usb_ep_autoconfig(). + * + * To support dual speed operation, a function driver provides descriptors + * for both high and full speed operation. Except in rare cases that don't + * involve bulk endpoints, each speed needs different endpoint descriptors. + * + * Function drivers choose their own strategies for managing instance data. + * The simplest strategy just declares it "static', which means the function + * can only be activated once. If the function needs to be exposed in more + * than one configuration at a given speed, it needs to support multiple + * usb_function structures (one for each configuration). + * + * A more complex strategy might encapsulate a @usb_function structure inside + * a driver-specific instance structure to allows multiple activations. An + * example of multiple activations might be a CDC ACM function that supports + * two or more distinct instances within the same configuration, providing + * several independent logical data links to a USB host. + */ +struct usb_function { + const char *name; + struct usb_gadget_strings **strings; + struct usb_descriptor_header **descriptors; + struct usb_descriptor_header **hs_descriptors; + + struct usb_configuration *config; + + /* REVISIT: bind() functions can be marked __init, which + * makes trouble for section mismatch analysis. See if + * we can't restructure things to avoid mismatching. + * Related: unbind() may kfree() but bind() won't... + */ + + /* configuration management: bind/unbind */ + int (*bind)(struct usb_configuration *, + struct usb_function *); + void (*unbind)(struct usb_configuration *, + struct usb_function *); + + /* runtime state management */ + int (*set_alt)(struct usb_function *, + unsigned interface, unsigned alt); + int (*get_alt)(struct usb_function *, + unsigned interface); + void (*disable)(struct usb_function *); + int (*setup)(struct usb_function *, + const struct usb_ctrlrequest *); + void (*suspend)(struct usb_function *); + void (*resume)(struct usb_function *); + + /* internals */ + struct list_head list; +}; + +int usb_add_function(struct usb_configuration *, struct usb_function *); + +int usb_interface_id(struct usb_configuration *, struct usb_function *); + +/** + * ep_choose - select descriptor endpoint at current device speed + * @g: gadget, connected and running at some speed + * @hs: descriptor to use for high speed operation + * @fs: descriptor to use for full or low speed operation + */ +static inline struct usb_endpoint_descriptor * +ep_choose(struct usb_gadget *g, struct usb_endpoint_descriptor *hs, + struct usb_endpoint_descriptor *fs) +{ + if (gadget_is_dualspeed(g) && g->speed == USB_SPEED_HIGH) + return hs; + return fs; +} + +#define MAX_CONFIG_INTERFACES 16 /* arbitrary; max 255 */ + +/** + * struct usb_configuration - represents one gadget configuration + * @label: For diagnostics, describes the configuration. + * @strings: Tables of strings, keyed by identifiers assigned during @bind() + * and by language IDs provided in control requests. + * @descriptors: Table of descriptors preceding all function descriptors. + * Examples include OTG and vendor-specific descriptors. + * @bind: Called from @usb_add_config() to allocate resources unique to this + * configuration and to call @usb_add_function() for each function used. + * @unbind: Reverses @bind; called as a side effect of unregistering the + * driver which added this configuration. + * @setup: Used to delegate control requests that aren't handled by standard + * device infrastructure or directed at a specific interface. + * @bConfigurationValue: Copied into configuration descriptor. + * @iConfiguration: Copied into configuration descriptor. + * @bmAttributes: Copied into configuration descriptor. + * @bMaxPower: Copied into configuration descriptor. + * @cdev: assigned by @usb_add_config() before calling @bind(); this is + * the device associated with this configuration. + * + * Configurations are building blocks for gadget drivers structured around + * function drivers. Simple USB gadgets require only one function and one + * configuration, and handle dual-speed hardware by always providing the same + * functionality. Slightly more complex gadgets may have more than one + * single-function configuration at a given speed; or have configurations + * that only work at one speed. + * + * Composite devices are, by definition, ones with configurations which + * include more than one function. + * + * The lifecycle of a usb_configuration includes allocation, initialization + * of the fields described above, and calling @usb_add_config() to set up + * internal data and bind it to a specific device. The configuration's + * @bind() method is then used to initialize all the functions and then + * call @usb_add_function() for them. + * + * Those functions would normally be independant of each other, but that's + * not mandatory. CDC WMC devices are an example where functions often + * depend on other functions, with some functions subsidiary to others. + * Such interdependency may be managed in any way, so long as all of the + * descriptors complete by the time the composite driver returns from + * its bind() routine. + */ +struct usb_configuration { + const char *label; + struct usb_gadget_strings **strings; + const struct usb_descriptor_header **descriptors; + + /* REVISIT: bind() functions can be marked __init, which + * makes trouble for section mismatch analysis. See if + * we can't restructure things to avoid mismatching... + */ + + /* configuration management: bind/unbind */ + int (*bind)(struct usb_configuration *); + void (*unbind)(struct usb_configuration *); + int (*setup)(struct usb_configuration *, + const struct usb_ctrlrequest *); + + /* fields in the config descriptor */ + u8 bConfigurationValue; + u8 iConfiguration; + u8 bmAttributes; + u8 bMaxPower; + + struct usb_composite_dev *cdev; + + /* internals */ + struct list_head list; + struct list_head functions; + u8 next_interface_id; + unsigned highspeed:1; + unsigned fullspeed:1; + struct usb_function *interface[MAX_CONFIG_INTERFACES]; +}; + +int usb_add_config(struct usb_composite_dev *, + struct usb_configuration *); + +/** + * struct usb_composite_driver - groups configurations into a gadget + * @name: For diagnostics, identifies the driver. + * @dev: Template descriptor for the device, including default device + * identifiers. + * @strings: tables of strings, keyed by identifiers assigned during bind() + * and language IDs provided in control requests + * @bind: (REQUIRED) Used to allocate resources that are shared across the + * whole device, such as string IDs, and add its configurations using + * @usb_add_config(). This may fail by returning a negative errno + * value; it should return zero on successful initialization. + * @unbind: Reverses @bind(); called as a side effect of unregistering + * this driver. + * + * Devices default to reporting self powered operation. Devices which rely + * on bus powered operation should report this in their @bind() method. + * + * Before returning from @bind, various fields in the template descriptor + * may be overridden. These include the idVendor/idProduct/bcdDevice values + * normally to bind the appropriate host side driver, and the three strings + * (iManufacturer, iProduct, iSerialNumber) normally used to provide user + * meaningful device identifiers. (The strings will not be defined unless + * they are defined in @dev and @strings.) The correct ep0 maxpacket size + * is also reported, as defined by the underlying controller driver. + */ +struct usb_composite_driver { + const char *name; + const struct usb_device_descriptor *dev; + struct usb_gadget_strings **strings; + + /* REVISIT: bind() functions can be marked __init, which + * makes trouble for section mismatch analysis. See if + * we can't restructure things to avoid mismatching... + */ + + int (*bind)(struct usb_composite_dev *); + int (*unbind)(struct usb_composite_dev *); +}; + +extern int usb_composite_register(struct usb_composite_driver *); +extern void usb_composite_unregister(struct usb_composite_driver *); + + +/** + * struct usb_composite_device - represents one composite usb gadget + * @gadget: read-only, abstracts the gadget's usb peripheral controller + * @req: used for control responses; buffer is pre-allocated + * @bufsiz: size of buffer pre-allocated in @req + * @config: the currently active configuration + * + * One of these devices is allocated and initialized before the + * associated device driver's bind() is called. + * + * OPEN ISSUE: it appears that some WUSB devices will need to be + * built by combining a normal (wired) gadget with a wireless one. + * This revision of the gadget framework should probably try to make + * sure doing that won't hurt too much. + * + * One notion for how to handle Wireless USB devices involves: + * (a) a second gadget here, discovery mechanism TBD, but likely + * needing separate "register/unregister WUSB gadget" calls; + * (b) updates to usb_gadget to include flags "is it wireless", + * "is it wired", plus (presumably in a wrapper structure) + * bandgroup and PHY info; + * (c) presumably a wireless_ep wrapping a usb_ep, and reporting + * wireless-specific parameters like maxburst and maxsequence; + * (d) configurations that are specific to wireless links; + * (e) function drivers that understand wireless configs and will + * support wireless for (additional) function instances; + * (f) a function to support association setup (like CBAF), not + * necessarily requiring a wireless adapter; + * (g) composite device setup that can create one or more wireless + * configs, including appropriate association setup support; + * (h) more, TBD. + */ +struct usb_composite_dev { + struct usb_gadget *gadget; + struct usb_request *req; + unsigned bufsiz; + + struct usb_configuration *config; + + /* internals */ + struct usb_device_descriptor desc; + struct list_head configs; + struct usb_composite_driver *driver; + u8 next_string_id; + + spinlock_t lock; + + /* REVISIT use and existence of lock ... */ +}; + +extern int usb_string_id(struct usb_composite_dev *c); + +/* messaging utils */ +#define DBG(d, fmt, args...) \ + dev_dbg(&(d)->gadget->dev , fmt , ## args) +#define VDBG(d, fmt, args...) \ + dev_vdbg(&(d)->gadget->dev , fmt , ## args) +#define ERROR(d, fmt, args...) \ + dev_err(&(d)->gadget->dev , fmt , ## args) +#define WARN(d, fmt, args...) \ + dev_warn(&(d)->gadget->dev , fmt , ## args) +#define INFO(d, fmt, args...) \ + dev_info(&(d)->gadget->dev , fmt , ## args) + +#endif /* __LINUX_USB_COMPOSITE_H */ |